Skip to main content
EV Evidence

Regulation · GB

Lowest-forecast 240-minute charging window

The rank-one continuous 240-minute window in the 2026-08-14 E2 forecast snapshot is 11:30–15:30 Europe/London. Across eight half-hour forecasts, its mean is 84.0 gCO2/kWh, with values from 83 to 86 gCO2/kWh. This four-hour result belongs to one GB forecast snapshot and is neither a general daytime rule nor evidence that a vehicle will charge for the full interval.

National Energy System Operator and partners: Carbon Intensity API national forecast

Reviewed

Key facts and evidence

For Great Britain, reviewed on 2026-08-13, the 2026-08-14 Europe/London forecast ranks 11:30–15:30 first among continuous 240-minute windows. Its eight half-hour forecasts average 84.0 gCO2/kWh, with a minimum of 83 and maximum of 86 gCO2/kWh; the result says nothing about another day or an EV's accepted energy.

National Energy System Operator and partners: Carbon Intensity API national forecast

Use the four-hour rank-one GB forecast interval from the 2026-08-14 Europe/London snapshot while retaining its duration and single-day boundary.

Why duration matters

A four-hour decision cannot be replaced by the lowest individual half-hour. E2 evaluates eight adjacent forecast slots and ranks their unrounded mean, preserving the whole requested duration.

Forecast spread, not actuals

The 83 to 86 gCO2/kWh range reports the minimum and maximum forecasts inside this window. It is not a measured-emissions range or a confidence interval.

Date-locked conclusion

The ranking remains locked to the 14 August 2026 Europe/London horizon. A later date may rank a different interval and must be assessed from its own forecast artefact.

What to do next

Preserve the four-hour duration when comparing this interval, and keep forecast intensity separate from vehicle charging duration or delivered energy.

Immediate action: Confirm that a fresh forecast and the vehicle's required outcome cover the intended decision date.

  • Stop using this interval for a different day, a shorter duration or a claim about energy actually delivered.

Professional hand-off

  • Use current manufacturer information for vehicle and chargepoint timing behaviour.

Questions this record can answer

What does the sourced evidence say about why duration matters?

A four-hour decision cannot be replaced by the lowest individual half-hour. E2 evaluates eight adjacent forecast slots and ranks their unrounded mean, preserving the whole requested duration.

What does the sourced evidence say about forecast spread, not actuals?

The 83 to 86 gCO2/kWh range reports the minimum and maximum forecasts inside this window. It is not a measured-emissions range or a confidence interval.

What does the sourced evidence say about date-locked conclusion?

The ranking remains locked to the 14 August 2026 Europe/London horizon. A later date may rank a different interval and must be assessed from its own forecast artefact.

Sources